Electrical transformer.



Patented 1an. I, |90I. A. F. BERRY.

ELECTRICAL TRANSFORMER.

(Application led July 28, 1900.)

2 Sheeis-Shant l.

(No Model.)

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No. 665,305. Patented. lan. I, |90I.

A. F. BERRY. l ELECTRICAL TRANSFDRMER.

(Application filed July 23, 1900.)

@No Modem .2 sheets-sheet z.

lUNITED STATES PATENT OEEicE.

ARTHUR FRANCIS BERRY, OF LONDON, ENGLAND.

ELECTRICAL TRANSFORNI ER.

SPECIFICATION forming part of Letters IDatent No. 665,305, dated January 1, 1901.

Application filed `l'uly 23, 1900.

To a/ZZ whom t may con/cern.:

Beit known that I, ARTHUR FRANCIS BERRY, a subject of the Queen of Great Britain and Ireland, residing at Ealing, London, in the county of Middlesex, England, have invented Improvements in Electrical Transformers, of which the following is a specification.

In the manufacture of electrical transformers it has heretofore been usual to construct the primary and secondary windings of two or more independent insulated conductors that have been separately wound in place in the transformer or have been formed into separate coils that have afterward been placed in the desired position in the transformer. These modes of construction are costly and slow and, moreover, require considerable skill and care to insure satisfactory results.

Now this invention has for its object to enable electrical transformers to be constructed in a cheaper, quicker, and easier manner than heretofore and with less dependence upon skilled labor. For this purpose the primary and secondary windings of an electrical transformer are made from a cable composed of conductors that are insulated from each other and are connected together at their ends by suitable coupling devices in such manner that some of the insulated conductors will be connected together in series or in parallel to form the primary winding or windings and the remainder will be connected together in series or in parallel to form the secondary winding or windings, the ratio between the number of turns com prising the sets of conductors forming the primary and secondary windings, respectively, being so designed as to give the desired ratio of electrical transformation. The cross-sectional shape of the cable and the number and arrangement of the insulated conductors of which it is composed and the method of insulation adopted can be variously modified as may be desired. Conveniently the cable maybe of circular section, the insulated conductors to form one windingsay the primary windingbeing arranged to form the central portion of the cable and inclosed within insulating material on the outside of which the conductors to form the other winding-say the secondary windingare laid and then covered by an outer covering of insulating material, the primary and Serial No. 24,618. (No model.)

secondary sets of conductors being thus arranged concentrically one Within the other. In this case each of the outer insulated conductors may be of segmental form and be composed of a number of bare wires or strips arranged together in parallel.- The cables may, however, be of square, rect-angular, or other section, it' desired.

A length of cable such as described can be readily formed into a coil either in situ in or on a transformer core or cores or separately therefrom, and the ends of the conductors to form each primary and secondary winding can be connected together by coupling or connecting devices of various kinds, so as to place the conductors of each set in series or multiple series with each other and produce the desired number of turns or couvolutions in either or both the primary and secondary coils.

Primary and secondary windings formed by a cable, as herein described, may advantageously be used in the construction of transformers having iron cores ot the kind described and shown in the specification of a former patent granted to lne-viz..No. 639,505.

Figures l and 2 of the accompanying illustrative drawings show, respectively,in side elevation and plan a transformer the iron core of which is formed of laminated-iron plates built up and arranged as described in the specification of my said former patent No. 639,505, and the winding of which is composed of a length of cable of the kind herein referred to. Fig. 3 shows in crosssection and to a larger scale than Figs. 1 and 2 one form which the cable may take. Figs. 4E and 5 are diagrams showing how the ends ot' the conductors of which the cable is composed may be coupled together to form primary and secondary windings. Eig. 6 is a separate view showing the detachable connection of the junction-pieces.

In the example shown the windings of the transformer consist of a single length of cable arranged in two layers that extend through rectangular holes in the laminatcdmetal plates a a', constituting the iron core of the transformer, the cable being composed of thirty-seven inner conductors of circular section that are numbered, respectively, from l to 37, forming the central portion of the IOO core, and are designed to serve as the primary winding or windings, and twelve outer conductors of segmental shape that are numbered, respectively, from 38 to 49 and are designed to serve as the secondary winding or windings. Each of the inner conductors l to 37 is selliarately insulated, and the annular rows of such conductors are insulated from each other and from the central conductor by interposed layers l) of suitable insulating material, so as to eifectually separate from each other adjacent conductors between which a considerable difference of electrical potential may exist. Each of the outer conductors 3S to 49 is also separately insulated, and the whole of them are insulated from the inner conductors by interposed insulating material c and covered by an outer layer d of insulating material. The ends of the several conductors in the example shown are ledinto a junction-box madein two parts e and f, the ends of the inner conductors l to 37 being led into and connected up in the lower part c of the said box, so as to place the several conductors in series with each other and form asingle primary winding,and the ends of the outer conductors being led into and connected up in any desired manner in the upper part f of the box to form the secondary winding or windings.

Fig. shows, diagrammatically, how the two sets ot' ends (marked, respectively, l to 37 and l1 to 37b) of the inner conductors l to 37 may be connected together. lu this case the end l of the central conductor l is connected to a terminal r, by which it can be connected to one pole of a source oi alternating-current supply. The otherend lb of this conductor is connected by a junction-piece l* to the end 2 of the conductor 2, the opposite end2b of which is similarly connected by a junction-piece 2* to the end'"L of the conductor 3, and so on, so that the whole of the conductors l to 37 are connected in series, the end 371 of the last conductor 37 being connected to another terminal g', by which it can be connected to the opposite pole of the said source of al ternatin g-cu rrent supply. Vilhen the ends of the conductors l to 37 have been thus coupled together, which maybe done by electric welding, the lower part c of the box may be filled with a suitable insulating material, either liquid or solid. The two sets of ends (marked, respectively, 3S to a9 and 3S" to 49) of the outer conductors 3S to a9 and located in the upper part fof the junctionbox may be similarly connected together by jun ction-pieces 38: to #18:11, as shown,diagram matically, in Fig. 5, when it is desired to couple the whole of the outer conductors in series to form a single secondary winding the ends of which are connected to terminals 7L 7L. The junction-pieces 38* to 48* may be detachably connected to the ends of the conductors 3S to i9, so as to admit of such conductors being readily coupled upin any other desired order, so as to lorm two or more secondary windings, as may be desired.

lVhen desired, a. safety device-for example, in the term of a metallic rape, screen, or shield 7o, Fig. 3, adapted to be earthed-may be inclosed in the layer c ol insulating matcrial between the primary and secondary windings, so as to extend longitudinally ci and within the cable.

That l claim isl. An electrical transformercomprisingan iron core composed oi a numberol lan'iinalediron plates, a length of cable extending through holes in said plates and composed ot' separately-insulated conductors,a1ul groups olf junction-pieces connecting' the said con ductors in the desired order to form combined primary and secondary windings, substantially as described.

2. An electrical transformer comprising an iron core composed of a number o built` up laminated-iron plates arranged radially around a center and each having a large hole therethrough,a length of cable wound to form a coil extending through the holes in said plates and composed ol' two sets ol separatelyinsulated conductors and junction -pieces connecting the said conductorsin the desired order to form primary and secondary windings, substantially as described.

3. An electrical transformer comprising an iron core composed ol a number ot' builtup laminated-iron plates arranged radially around a center and each having alarge hole therethrough, and a length oll cable wound to form a coil extending through the holes in said plat s and composed of two concentrically-arranged sets ot' separately-insulated conductors coupled up to form primary and secondary windings, substantially as described.

il. An electrical transformer comprising` an iron core composed ol a number of builtup laminated-iron plates arranged radially around a center and each having a large hole therethrough, and a length of cable wound to form a coil extending through the holes in said plates and composed of two concentrically-arran ged sets of separately-insulated conductors, the conductors in the inner set being arranged in annular rows around a center one, and the conductors in the outer set being annularly arranged around the inner ones, concentric layers of insulating material between the several annular rows of conductors, and junction-pieces coupling up the cond uctors ot' the two sets to form the desired primary and secondary windings, substantially as described.

5. ln an electrical transformer, a cable composed of sets ot insulated conductors connected up to form primary and secondary windings, and a safety or earthing device arranged longitudinally ot' and within said cable and between the said windings, substantially as described.

6. In an electrical transformer, a cable com- TOO IIO

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posed of concentric sets of insulated conductors connected up to form primary and secondary windings, and a, metallic safety or earthing device arranged longitudinally of and Within said cable and inelosing the inner or primary Winding or windings and located between the two sets of conductors, substantially as described.

7. An electrical transformer comprising a laminated-iron core, a length of cable Wound on said core and composed of two seis of separately-insulated conductors, junction -box located on the top of said transformer and made in parte into which the ends of the sets oit conductors are respectively led, and groups of junction-pieces connecting the ends of said conductors in tlie respective parts of said junction-box te form the required primary and secondary windings, substentiallyns described.

Signed et 77 Cornhill, in the city of London, England, this lltll'daly of July, 1900.

ARTHUR FRANCIS BERRY. lilitnesses:

WM. 0. BROWN, EDMUND S. SNEWIN. 

